Among the birth defects related to prenatal exposure to alcohol, the most worrisome, and the most costly to society, are impaired cognitive and intellectual functioning. Although the existence of the effect is well established, a number of important issues regarding the parameters of the problem remain to be explored. Questions about threshold of effect, vulnerability, and risk associated with exposure in different periods in gestation are sources of concern to society, to women, and to those who counsel women who are pregnant or who will become pregnant. Research on the topic is difficult, time consuming and costly. A large and rich database is available as a result of the Cleveland prospective study of alcohol related birth defects. This research group has followed to age four years, ten months, a cohort of children for whom there are available detailed short term recall records of maternal alcohol use starting at the first antenatal visit. The mother's history of alcohol abuse was also measured as were other variables that might confound the relationship of prenatal alcohol exposure and child development. The set of data collected through age three years is now being analysed. This proposal is for the statistical analysis of the data gathered just prior to the age of school entry for approximately 265 children. Included are an individually administered standardized intelligence test, a measure of attention deficit, a neurological examination, parent and examiner behavior ratings, and size measurements. Data collected also include information about current maternal alcohol use. These will be used to describe the direct effect of current alcohol use on maternal childrearing behavior and to describe the persistence of maternal alcohol use and abuse through a five year period.